Ruminant neurological disease: a retrospective cohort study

Abstract

Between January 2006 and June 2016, 96 ruminants with neurological signs were donated to the Scottish Centre for Production Animal Health and Food Safety (SCPAHFS), University of Glasgow, by veterinarians in the field representing 5.4 per cent of all submissions. Forty-seven different neurological presenting signs were reported with 79 per cent of the donated patients presenting with abnormal gait. All cases presenting with abnormalities in more than 4 out of 10 neurological categories died or were euthanased on welfare grounds. Calves were significantly more likely to present with neurological disorders than adult cattle compared with the proportion of calves: cows in the Scottish cattle population and total case population donated to SCPAHFS. Lesions were most commonly localised to the spinal cord in sheep 47 per cent (16), the peripheral nervous system in cattle 45 per cent (28) and to the brain in the overall population 41 per cent (39). The most common aetiology of neurological pathologies observed was infectious or inflammatory 28 per cent (27). Definitive diagnoses could be reached in 84 per cent (81) of patients. When postmortem reports were available, they produced a diagnosis in 70 per cent (52) of cases and contradicted clinical diagnoses in 38 per cent (26) of cases. The most frequently diagnosed conditions in ruminants over the 10 years were spastic paresis, vertebral osteomyelitis and listeriosis.

Central nervous system diseases of cattle in Georgia, 2001–2017

“…(2), MCF (2), bovine coronavirus (4), and bovine rotavirus (1); IHC for rabies (2), encephalomyocarditis virus (1), Listeria spp. (1), and Toxoplasma gondii (1); PCR for eastern and western equine encephalitis virus (2) and West Nile virus (1); aerobic culture (7) or Listeria spp. culture (5); and virus isolation (9).…”

Neurological disease in ruminants

“…13 Husbandry short-comings, in particular concerning nutrition, remain common as demonstrated by the relative frequency of listeriosis shown by Giles and others, 6 as well as their finding of cerebro-cortical necrosis, a condition commonly associated with concentrate feeding-induced thiamine deficiency. Other examples include botulism, lead or organophosphate poisoning and water intoxication after a period of water deprivation.…”

“…Truchet and others 12 highlight the role of postmortem examination in the diagnosis of emerging or new conditions or those with a herd- or flock-wide impact, as does the article by Giles and others. 6 …”

“…There are a number of conditions with an iatrogenic aetiology, such as closantel toxicosis reported by Giles and others, 6 or incorrect injection technique of oil‐based vaccines leading to compressive lumbar myelopathy 13 . Husbandry short‐comings, in particular concerning nutrition, remain common as demonstrated by the relative frequency of listeriosis shown by Giles and others, 6 as well as their finding of cerebro‐cortical necrosis, a condition commonly associated with concentrate feeding‐induced thiamine deficiency. Other examples include botulism, lead or organophosphate poisoning and water intoxication after a period of water deprivation 14…”

“…In conclusion, neurological disorders affect a wide range of aspects of livestock production. Because typically the herd or flock, rather than just the individual animal, has to be considered, it is fitting that Giles and others 6 emphasise the benefit of combining clinical assessment with postmortem examination.…”